• Journal of the Korean institute of surface engineering
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• v.29 no.2
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• pp.93-99
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• 1996

In this work BN thin films were deposited on Si substrate by R. F. sputtering method at $200^{\circ}C$ and in Ar + $N_2$ mixed gas atmosphere. In order to investigate the effect of ion bombardment on substrate for c-BN bonding, substrate bias voltage was applied. The optimum substrate bias voltage for c-BN bonding was determined by FTIR analysis on specimens which were deposited with various bias voltages. Then BN thin film was deposited with this optimum condition and its phase, morphology, chemical composition, and refractive index were compared with those of BN film which was deposited without bias voltage. FTIR results showed that BN films deposited with substrate bias voltage were composed of mixed phases of c-BN and h-BN, while those deposited without bias voltage were h-BN only. When pure Ar gas was used for sputtering gas, BN films were delaminated easily from substrate in air, while when 10% $N_2$ gas was added to the sputtering gas, although c-BN specific infrared peak was reduced, delamination did not occur. GXRD and TEM results showed that BN films were amorphous phases regardless of substrate bias voltage, and AES results showed that the chemical compositions of B/N were about 1.7~1.8. The refractive index of BN film deposited with bias voltage was higher than that without bias voltage. The reason is believed to be the existence of c-BN bonding in BN film and the higher density of film that deposited with the substrate bias voltage.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.7
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• pp.1420-1428
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• 2017

It is difficult to guarantee the reliability of the algorithm due to the difference of the sampling frequency among the various ECG databases used for the R wave detection in case of applying to different environments. In this study, we propose an optimal threshold setting method for R wave detection according to the sampling frequency of ECG signals. For this purpose, preprocessing process was performed using moving average and the squaring function based the derivative. The optimal value for the peak threshold was then detected according to the sampling frequency by changing the threshold value according to the variation of the signal and the previously detected peak value. The performance of R wave detection is evaluated by using 48 record of MIT-BIH arrhythmia database. When the optimal values of the differential section, window size, and threshold coefficient for the MIT-BIH sampling frequency of 360 Hz were 7, 8, and 6.6, respectively, the R wave detection rate was 99.758%.

• KSBB Journal
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• v.18 no.1
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• pp.39-44
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• 2003

A Gene content phylogenetic tree and a 16s rRNA based phylogenetic tree were compared for 33 whole-genome sequenced procaryotes, neighbor joining and bootstrap methods (n=1,000). Ratio of conserved COG (clusters of orthologous groups of proteins) to orthologs revealed that they were within the range of 4.60% (Mezorhizobium loti) or 56.57% (Mycopiasma genitalium). This meant that the ratio was diverse among analyzed procaryotes and indicated the possibility of searching for useful genes. Over 20% of orthologs were independent among the same species. The gene content tree and the 16s rDNA tree showed coincidence and discordance in Archaeabacteria, Proteobacteria and Firmicutes. This might have resulted from non-conservative genes in the gene content phylogenetic tree and horizontal gene transfer. The COG based gene content tree could be regarded as a midway phylogeny based on biochemical tests and nucleotide sequences.

• Bulletin of the Korean Mathematical Society
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• v.45 no.4
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• pp.663-670
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• 2008

In this paper, the aim is to solve the neutral delay differential equations in the following form using multiquadric approximation scheme, (1) $$\{_{\;y(t)\;=\;{\phi}(t),\;\;\;\;\;t\;{\leq}\;{t_1},}^{\;y'(t)\;=\;f(t,\;y(t),\;y(t\;-\;{\tau}(t,\;y(t))),\;y'(t\;-\;{\sigma}(t,\;y(t)))),\;{t_1}\;{\leq}\;t\;{\leq}\;{t_f},}$$ where f : $[t_1,\;t_f]\;{\times}\;R\;{\times}\;R\;{\times}\;R\;{\rightarrow}\;R$ is a smooth function, $\tau(t,\;y(t))$ and $\sigma(t,\;y(t))$ are continuous functions on $[t_1,\;t_f]{\times}R$ such that t-$\tau(t,\;y(t))$ < $t_f$ and t - $\sigma(t,\;y(t))$ < $t_f$. Also $\phi(t)$ represents the initial function or the initial data. Hence, we present the advantage of using the multiquadric approximation scheme. In the sequel, presented numerical solutions of some experiments, illustrate the high accuracy and the efficiency of the proposed method even where the data points are scattered.

• Bulletin of the Korean Chemical Society
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• v.28 no.6
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• pp.1031-1034
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• 2007

The R- and Z-substituent effects for the gas-phase thermal decompositions of carbamates, R2NC(=O)- OCH2CH2Z, have been investigated theoretically at B3LYP level with 6-31G(d) and 6-31++G(d,p) basis sets. Both the Z- and R-substituent effects on reactivity (ΔH≠) were well consistent with experimental results, although the R-substituent effect was underestimated theoretically. No correlations were found between activation enthalpies and reaction enthalpies. The substituent effects on reactivity seemed to be complicated at a glance, but were understandable by concurrent electronic and steric factors. Variations of bond lengths at TS structures were well correlated with the Taft's σ* values and the TS structures became tighter as the Zsubstituent became a stronger electron-acceptor (δσ* > 0). However the effects of R-substituents on the TS structures were much smaller when compared to those of Z-substituents.

• Journal of the Korean Data and Information Science Society
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• v.14 no.2
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• pp.385-391
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• 2003

A sequence of n Bernoulli trials which violates the constant success probability assumption is termed as "Poisson trials". In this paper, the recurrence formula for the r-th central moment of number of successes with n Poisson trials is derived. Romanovsky's method, based on the differentiation of characteristic function, is used in the derivation of recurrence formula for the central moments of conventional binomial distribution. Romanovsky's method is applied to that of Poisson trials in this paper. Some central moment calculation results are given to compare the central moments of Poisson trials with those of conventional binomial distribution.

• Near Infrared Analysis
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• v.2 no.1
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• pp.37-42
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• 2001

Near infrared spectroscopy (NIRS) was applied to determination of the lipid content of the compost during the compost fermentation of tofu (soybean0curd) refuse. The absorption of lipid observed at 5 wavelengths, 1208, 1712, 1772, 2312 and 2352 nm on the second derivative spectra. To formulated a calibration equation, a multiple linear regression analysis was carried out between the near-infrared spectral data and on the lipid content in the calibration sample set (sample number, n=60) obtained using Soxhlet extraction method. The value of the multiple correlation coefficient (R) was 0.975 when using the wavelengths of 1208 and 1712 nm were used in the calibration equation. To validate the calibration equation obtained, the lipid content in the validation sample set (n=35) not used for formulating the calibration equation was calculated using the calibration equation, and compared with the value obtained using the Soxhlet extraction method. Good agreement was observed between the results of the Soxhlet extraction method and those values of the NIRS method. The simple correlation coefficient (r) and standard error of prediction (SEP) were 0.964 and 0.815 %, respectively. suitability of the lipid content as an indicator of the compost fermentation of tofu refuse was also studied. The decrease of the lipid content in the compost corresponded to the decrease of the total dry weight of the compost in the composter. The lipid content was a significant indicator of the compost fermentation. The NIRS method was applied to measure the time course of the lipid content in the compost fermentation and good results were obtained. The study indicates that NIRS is a useful method for process management of the compost fermentation of tofu refuse.

• Journal of Food Hygiene and Safety
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• v.28 no.2
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• pp.181-187
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• 2013

Identification of main ingredients in starches has been investigated using physicochemical analysis method mainly. However, physicochemical properties such as particle size have limitations in determining the differences among mixed starches. Therefore, we developed a molecular biological method to identify materials used in starch, as a sample, 11 kinds of starches including sweet potato starch, potato starch, corn starch, and tapioca starch. DNeasy plant mini kit, magnetic DNA purification system, and CTAB methods were used to extract DNA from samples. After gene extraction, whole genome amplification (WGA) was performed to amplify the extracted DNA. Species-specific primers were used as followings: ib-286-F/ib-286-R (105 bp), Pss 01n-5'/Pss 01n-3' (216 bp), SS11b 3-5'/SS11b 3-3' (114 bp), and SSRY26-F/SSRY26-R (121 bp) gene for sweet potato, potato, corn, and tapioca, respectively. In this study, we could confirm the main ingredients using WGA and PCR method.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.30A no.11
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• pp.113-121
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• 1993

In the formation of the shallow p$^{+}$-n junction, the preamorphization method by As$^{+}$ ions was applied in order to avoid the boron channeling effect which is occured during the B$^{+}$ implantation especially with low energy. By As$^{+}$ pre-implant with 60KeV energy and 2*10$^{14}$ cm$^{-2}$ dose, the channelinf of B$^{+}$ ions implanted with 10keV/1.5*10$^{14}$ cm$^{-2}$ can be avoded completely. After the RTA of 1050.deg. C and 10sec, the junction depth was 0.14.mu.m, the leakage current was 20nA/cm$^{2}$(at-5V bias) and the sheet resistance was 107.OMEGA./ㅁ. And the preamorphized Si layer was changed into the perfect crystal si after the RTA.r the RTA.

• Journal of the Korean Chemical Society
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• v.38 no.11
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• pp.827-832
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• 1994

The crystal structure of bis(N-methylphenazinium) bis(oxalato)palladate(II) has been determined by X-ray crystallography. Crystal data: ((C_{13}H_{11}N_2)_2[Pd(C_2O_4)_2]) $M_w$ = 672.93, Triclinic, Space Group P1 (No = 2), a = 7.616(8), b = 9.842(3), c = $20.335(7)\AA$, $\alpha$ = 103.53(3), $\beta$ = 90.00(5), $\gamma$ = $112.38(5)^{\circ}$, Z = 2, $V = 1363(2){\AA}^3\;D_c = 1.639\;gcm^{-3},\;{\mu} = 7.3\;cm^{-1},\;F(000) = 680.0$. The intensity data were collected with $Mo-K\alpha$ radiation (${\lambda}$= 0.7107\;\AA)$ on an automatic four-circle diffractometer with a graphite monochromater. The structure was solved by Patterson method and refined by full matrix least-square methods using Killean & Lawrence weights. The final R and S values were $R = 0.069,\;R_w = 0.050,\;R_{all} = 0.069$ and S = 5.45 for 3120 observed reflections. Both cation and anion complexes are essentially planar and have dihedral angles of 6.3(6) and $57.06(6)^{\circ}$ between their planes. The planar complex anions are sandwiched between slightly bent cations. The interplanar separations of two triads are 3.328 and 3.463 $\AA$, respectively. The triads are stacked along b-axis, but their orientations are different based on dihedral angle $59.08(9)^{\circ}$ of two complex anions.